OSLO (Reuters) - Sharing a border of 1,600 km (1,000 miles), with close to 80 crossings, Norway and Sweden face some of the challenges that Ireland and Northern Ireland may experience when the United Kingdom leaves the European Union.

On Wednesday Britain published a paper arguing there should be no border posts or immigration checks between Ireland and the British province of Northern Ireland after Brexit. It is also keen to keep disruption to trade to a bare minimum.

This are familiar issues for EU member Sweden and non-EU Norway.

Norwegians and Swedes have enjoyed open-border travel since before the EU came into existence - as have the British and Irish, who hope to maintain that uninterrupted free movement of people after Brexit too.

Thousands of Swedes and Norwegians cross their shared border every day to work, to shop or for leisure.

The Nordic neighbours tightened travel document checks after a large inflow of migrants into Europe in 2015 - but the number of arrivals subsided, and now passport checks are again rare.

But Norway has remained outside the EU’s customs union - and British Prime Minister Theresa May’s government has indicated it also wants to leave the customs union after Brexit.

To keep up the flow of goods and enjoy the benefits of low or zero tariffs when companies trade, Norway has committed to harmonise its commercial rules with those of the EU.

However, individuals entering Norway face strict limits on what they can bring in. Tariffs apply for a wide range of items, including alcohol, tobacco, meat and other goods, with only small quotas being exempt from payments.

CHECKING NUMBER PLATES

Another challenge is that, while one major Swedish-Norwegian crossing is staffed with police and customs officials, the vast majority of roads between the countries have no permanent presence of either.

In one key test area, cameras were involved in the more than half the cases where violators were caught, the Norwegian customs authority said in late 2016, and the government has decided that all crossings will now get cameras by 2019.

In Norway, those who break the rules face stiff penalties even for small transgressions. For example, if you smuggle more than 10 litres of wine, on top of your allowed quota of six bottles, you get fined 3,400 Norwegian crowns ($440) and the alcohol gets confiscated.

Those smuggling larger quantities face a term in prison.

In its latest paper, Britain has said it does not favour electronic surveillance on its border with Ireland, though it has not ruled out some technology-based solutions post-Brexit.

Ireland, which is keen to avoid any hard border with Northern Ireland, welcomed the British paper.

Last week Irish Prime Minister Leo Varadkar called for the EU and Britain to find “unique solutions” to their Brexit logjam, including a bespoke customs union to govern trade between his country and the United Kingdom.